Port all dbus server/client to to zbus

Seems to generally be working well. May still need a few fixes.

src/dbus_service.rs

@@ -0,0 +1,53 @@
+use futures::prelude::*;
+use gtk4::glib::{self, clone};
+use std::cell::Cell;
+use zbus::fdo::{DBusProxy, RequestNameFlags, RequestNameReply};
+use zbus_names::WellKnownName;
+
+pub async fn create<
+    F: Fn(zbus::ConnectionBuilder<'static>) -> zbus::Result<zbus::ConnectionBuilder<'static>>,
+>(
+    well_known_name: &'static str,
+    serve_cb: F,
+) -> zbus::Result<zbus::Connection> {
+    let well_known_name = WellKnownName::try_from(well_known_name)?;
+
+    let connection = serve_cb(zbus::ConnectionBuilder::session()?)?
+        .build()
+        .await?;
+    let dbus_proxy = DBusProxy::new(&connection).await?;
+    let mut name_owner_changed_stream = dbus_proxy.receive_name_owner_changed().await?;
+
+    let flags = RequestNameFlags::AllowReplacement.into();
+    match dbus_proxy
+        .request_name(well_known_name.as_ref(), flags)
+        .await?
+    {
+        RequestNameReply::InQueue => {
+            eprintln!("Bus name '{}' already owned", well_known_name);
+        }
+        _ => {}
+    }
+
+    glib::MainContext::default().spawn_local(clone!(@strong connection => async move {
+        let have_bus_name = Cell::new(false);
+        let unique_name = connection.unique_name().map(|x| x.as_ref());
+        while let Some(evt) = name_owner_changed_stream.next().await {
+            let args = match evt.args() {
+                Ok(args) => args,
+                Err(_) => { continue; },
+            };
+            if args.name.as_ref() == well_known_name {
+                if args.new_owner.as_ref() == unique_name.as_ref() {
+                    eprintln!("Acquired bus name: {}", well_known_name);
+                    have_bus_name.set(true);
+                } else if have_bus_name.get() {
+                    eprintln!("Lost bus name: {}", well_known_name);
+                    have_bus_name.set(false);
+                }
+            }
+        }
+    }));
+
+    Ok(connection)
+}